Also have been there and done that for a similar distance......Time for a new crank probably, at least I have never had any luck getting one to re-seat and stay tight even using loctite on the bolt.A Throttle is very useful. Went out last night with a fellow biker and stopped off at a brewery after dark when my crank fell off. The crank bolt had come loose a ways back, fell out, don't know where. Surprised I didn't notice it earlier. I was able to ride back home 10 miles under throttle.